(1) Field of the Invention
This invention relates to agricultural planters and more particularly to planters for crops planted in rows.
(2) Description of the Prior Art
Agriculture today is mechanization. Mechanization requires uniformity. This is particularly true of planting because the seeds must all be planted so that the seedlings emerge from the ground the same time. Not only must the seedlings emerge from the ground at the same time, but ten days or two weeks later all seedings must have approximately a uniform height, so they can be cultivated in a uniform fashion. At a later time, it is necessary that the plants all mature at the same time so they can be mechanically harvested at the same time.
To achieve this uniformity in plants, it is essential that the seeds be planted with great precision. Not only is it necessary that each seed be uniformly spaced from other seeds, but also that the seed depth be achieved with great precision. Not only must the depth of the seed in the furrow be precise, but also the depth of the seed from the top of the ground of the original seed bed should be precise. When the seed bed is planted, normally there will be a layer of dry soil above the planting zone. The moisture content of the seed bed will vary with the depth. Therefore, for optimum results, as well as uniform results, it is desired to plant the seed at a certain particular depth from the original surface of the seed bed, and also have it covered so that it is at a certain depth in the seed bed after planting.
For row crops two basic types of planters are commonly used.
The first type can be characterized as the tool bar carried planter. With this arrangement, the planters for each row are rigidly attached to a tool bar, which extends over several rows; for example: eight rows. If the height of the eight rows is not uniform, the seed will be deposited in some rows too shallow, and in other rows too deeply.
Another type of planter is commonly known as a drag box planter. With this type planter, the lister or double mold is rigidly attached to a tool bar. A planter assembly including a seed box, opening plow, and covering mechanism is drafted or towed behind the lister. However, since the weight of the seed in the seed box is supported by the planting mechanism, which is towed behind the lister, the depth of the seed will vary with the amount of seed in the seed box.
Before this application was filed, a search was made in the United States Patent and Trademark Office. This search revealed the following patents:
McINTYRE, U.S. Pat. No. 2,416,189 PA1 TANKE, U.S. Pat. No. 2,687,238 PA1 BUHR, U.S. Pat. No. 2,698,114 PA1 CAYTON ET AL., U.S. Pat. No. 3,749,035 PA1 REUTER, U.S. Pat. No. 4,037,755 PA1 BAILEY ET AL., U.S. Pat. No. 4,214,537
CAYTON ET AL discloses a planter having the seed box supported by the tool bar while the opening plow and covering mechanism is drafted behind the tool bar by a parallel motion linkage. CAYTON ET AL does not disclose a plow to remove dry soil from the seed bed before planting the seed. Also, the gage wheels 66 are not the most forward element mounted upon the furrow forming unit.
McINTYRE discloses an opening plow and covering mechanism supported by parallel linkage mechanism, however, the dry soil would be removed by the plow or sweep 20 mounted rigid to the tool bar. Also, McINTYRE does not appear to have gage wheels.
The other four patents do not appear as pertinent as the CAYTON ET AL and McINTYRE patents as specifically discussed above. The pertinency of these other four patents appear to be mainly that the searcher, in making a search for this invention, considered they might be of some interest.